15-phenyl-beta-methylpentadecanoic-acid and phosphinothricin

A rapid analytical method for residues of the herbicide glufosinate [DL-homoalanin-4-yl (methyl)phosphinic acid] and its metabolite (MPPA: 3-methylphosphinicopropionic acid) in soybeans and corns was developed by improving the bulletin method. Fifty mL of solution extracted with water (corresponding to 2 g of the sample) was loaded on a column packed with 5 mL of anion exchange resin, and then the trapped glufosinate and MPPA were eluted with 40 mL of 50% acetic acid. After the derivatization of glufosinate and MPPA with trimethyl orthoacetate, the derivatives were purified and separated on a silica gel cartridge column. The determination of the derivatives was performed with a GC-FPD. The detection limits for glufosinate and MPPA were 0.01 microgram/g and 0.005 microgram/g, respectively. The recoveries of glufosinate from soybeans and corns were 86.3-92.0%, and those of MPPA were 86.5-95.2%.

Topics: Aminobutyrates; Chromatography, Gas; Fatty Acids; Food Analysis; Glycine max; Herbicides; Pesticide Residues; Zea mays